The present invention relates to a slide track assembly and, more particularly, to a three-part type slide track assembly permitting stable sequential retraction and extension.
A conventional three-part type slide track assembly includes an outer track, a middle track, and an inner track. In an example of a three-part type slide track assembly for a cabinet type server, the outer track is mounted to a frame, the inner track is fixed to a side of the server, and the middle track serves as a loading track and is mounted between the outer track and the inner track, permitting the server to move in a range. Furthermore, the inner track and the middle track can slide relative to the outer track to permit the server to be pulled outwards or pushed inwards.
In a conventional three-part type slide track assembly, the middle track includes a sliding groove receiving a movable cylindrical positioning peg. Each of the outer track and the inner track includes a locking plate. The cylindrical positioning peg includes a plurality of cylindrical sections having different diameters to cooperate with the sliding groove and the locking plates for controlling locking and unlocking of the inner track, the middle track, and the outer track, permitting sequential extension and retraction of the inner track and the middle track relative to the outer track. However, the cooperation between the cylindrical positioning peg having the cylindrical sections of different diameters, the sliding grooves, and the locking plates are unstable, and the structural strength is adversely affected.
Thus, a need exists for a novel three-part type slide track assembly permitting stable sequential retraction and extension.